§1. Let

denote a linear substitution of non-vanishing determinant; and let the roots k∈ of its characteristic equation

be for the present assumed distinct. Then with each root k∈ is associated an invariant point or pole P∈, and a linear invariant, or invariant (n−2)-plane ξ∈. If the n points P∈ do not lie on an (n−2)-plane, the determinant of their coordinates,

(Received November 04 1916)
(Accepted December 10 1916)